8 Layers Rigid PCB Board with White and Blue SM
In the process of hole metallization for PCB production, many electrochemical expertise is involved and many chemical drugs are used. The following is the specific efficacy and configuration method of these chemical solutions used in our production.
1. Pre-leaching solution: the pharmaceutical solution used for double-sided rigid pcb board pretreatment is referred to as pre-leaching solution for short (its composition is kh-21-l). The main function is to maintain the acidity and specific gravity of KH-22-L tank fluid before PTH activation.It also ensures uniform infiltration (and charge adjustment) of the through-hole wall and prevents harmful impurities from entering the kh-22-l.
Ratio of working fluid per liter: the optimal range of KH-21-L 220-240g/L 240g/L37% reagent HCI (hydrochloric acid) 2-5% (v/v) 4% distilled water residue.
Preparation method: first, inject 1/2 volume of distilled water into the tank, and then add the required amount of KH-21-l, and make it completely dissolved. Slowly add the desired amount of hydrochloric acid and stir well. Finally, adjust to the specified volume with distilled water. The liquid tank shall be a special container provided by dongming dm-2120 hole metallization box or a container made of polyvinyl chloride, polypropylene and PVC materials. The working temperature can be controlled at room temperature, and the processing time is 0.5-2 minutes. Liquid maintenance can be supplemented according to the amount of treatment, and 39g kh-21-l and 3.4ml 37% HCI should be added to the tank for each square meter of circuit board treatment.Replace the tank when the solution appears cloudy or dark green.
2. Activation solution: the main component is KH-22-L.KH-22-L is a new type of acidic colloid palladium activator. The colloid particles in this new type of activator can penetrate into micropores and be uniformly adsorbed on the surface of non-conductors.It provides sufficient and effective catalytic activity core for subsequent electroless copper plating.
Ratio of working fluid per liter: the best value in range
KH-21-L, 220-240g/L 240g/L
Reagent HCI 37%, 2-5%(v/v)4%
Residual distilled water
Preparation method: first in the plate groove pull into 1/2 tank of distilled water, then the required KH-21-L was added and completely dissolved. Slowly add the desired amount of HCI and stir well. And then you add the amount of CS-22-K that you need. Finally, 0.5% dilute hydrochloric acid solution was used to adjust the tank solution to the specified volume and mix well.The activation fluid is now configured. The liquid maintenance can be supplemented according to the amount of rigid pcb boards processed. 5.5ml KH-22-L should be added for each square meter of circuit board material processed.